Mask ink is printed by using an array of ink jet nozzles (hereinafter—nozzles).
The array can include nozzles that may malfunction. A malfunctioning nozzle that does not print at all is referred to as a missing nozzle.
In most application the jetted ink is allowed to spread so that it fills the gaps or voids resulting from a missing nozzle. Thus, the ink spreads enough on the substrate to overcome missing nozzles.
Examples of such usages are:
a. When using a viscose ink such as a solder mask ink a missing nozzle can be noticed on the printed object.
b. Printing 3D model, when there is a missing nozzle instead of printing one object there will be two objects
c. Printing conductive lines, when there is a missing nozzle there will be a cut in the line and the panel will be defected.
There is a growing need to provide efficient substrate printing methods. Other applications where ink-jet may be used for manufacturing may also suffer from missing nozzles. Some examples of such occurrences:
a) Electronic circuit trace printing with conductive material: A missing nozzle will create an open circuit or a trace that does not have the expected conductivity characteristics
b) Etch resist printing: The areas to be protected by the jetted material do not get the required protection and are etched away
c) Objects that are created using ink-jet methods may result in disconnected parts due to the missing nozzles